Preparation and tribological properties of TiAl matrix composites reinforced by multilayer graphene

This paper reports on preparation technique and tribological properties of multilayer graphene (MLG) reinforced TiAl matrix composites (GTMC). GTMC are successfully prepared by spark plasma sintering (SPS). Structural characterization of starting MLG and the sintered GTMC are performed using Raman spectroscopy and field emission scanning electron microscopy, which indicates that MLG homogeneously distributes in GTMC. Tribological studies suggest that MLG plays an important role in decreasing friction coefficients by a factor of 4 and wear by almost 4-9 times of magnitude. Such marked reductions are attributed to the fact that MLG easily shears and forms a conformal anti-wear protective layer on the sliding contact interfaces, thus drastically reduces the friction coefficients and wear rates of GTMC. MLG can actually act as an effective reinforcement and lubricant phase in GTMC.